The present invention relates to a sliding cover for receptacles or canisters used on duplicating apparatus, for receiving duplicating fluid such as an ink or dye.
The invention relates more particularly to a sliding cover that has a discharge opening which forms an interconnection with a duct for distribution of dye within a duplicating machine and which has a reservoir formed around the interconnection to retain duplicating fluid which may have leaked from the interconnection.
Dye or ink receptacles, which contain the duplicating fluid for use on duplicating machines, are usually directly inserted into the duplicating apparatus, after their closure has been removed. The duplicating or printing fluid is conducted to the distributing nozzles in the duplicating apparatus by means of a duplicating fluid duct. This is accomplished, depending on the duplicating apparatus, by use of pumps or by forcing the duplicating fluid out of the receptacle, under pressure, and into the ducts.
One particular method of accomplishing the pumping of the fluid is by filling a tube with the duplicating fluid and connecting the tube to a pump.
In simpler duplicating apparatus, a canister is fitted with a sliding bottom. The bottom is pressed up into the canister by means of a piston rod which is normally driven by a screw thread and which results in the fluid being pushed out through a canister nozzle or outlet located in the cover. This nozzle or outlet is interconnected with a duct system through which the fluid is conducted to the distributing nozzles.
Another device employs a base plate which is raised by means of a toothed gearing or similar device and supports the fluid canister. In such a device, the canister is provided with a sliding cover having an opening provided with a lip which can be interconnected with the duct system. In this device, the base plate is raised, the canister is forced to slide up past the sliding cover, whereby the fluid is forced out of the cover opening and into the duct system.
The distributing nozzles are normally arranged between two rollers over which the retiform dye carrier is placed together with the pattern sheet. The pressure on the fluid in the canister distributes the fluid to the nozzles for dispersal.
A problem which is encountered when using the last described method of forcing fluid out of the canister by raising the canister past the cover, is that there occurs leakage of dye or ink past the interconnection of the outlet with the duct. Although toroidal or similarly shaped lips have been used around the discharge opening to help insure a tight interconnection with the ducts, an absolutely fluid-tight closure can thereby not be guaranteed. Any duplicating fluid which leaks from the interconnection has, in the past, at least, caused the machine to become excessively soiled, and required frequent shutdowns to undertake an effective cleaning operation.
It has been found that complete removal of the dye or ink which has leaked into the machine often is not possible and the duplicating devices soon require repair.